D.C. Mayor Muriel E. Bowser (D) pointed to data Thursday showing a sharp drop in the number of the youngest students who are meeting literacy benchmarks to reinforce her point that there is an urgent need to reopen schools, even as the city and the teachers union fail to agree on how to safely bring teachers and students into buildings.

D.C. Public Schools said data shows a decline of 11 percentage points in the number of kindergartners through second graders meeting literacy goals at the start of the school year compared to a year ago. The data is based on virtual assessments administered to students by their teachers one-on-one this fall. It is unclear how taking the tests remotely affected the outcomes and if improved remote learning in the fall is boosting student performance.

“For all the kids who may never catch up from missing seven months of school — and maybe the whole academic year if their government does not have a plan — this is what we are talking about,” Bowser said.

The city’s plan for a phased reopening is due to start in two weeks, but parents and teachers fear chaos with staff members being reassigned, virtual classes interrupted, and lack of agreement on the kinds of masks that will be provided and who signs off on a building’s inspection.

The city plans to bring 7,000 elementary students most at risk for academic failure back to classrooms on Nov. 9, the start of the second term. Another 14,000 children would be allowed to return to their elementary campuses, but they would continue with virtual learning under the supervision of nonteaching staff.

Middle and high school staff members will be assigned to supervise elementary students doing virtual learning in classrooms, angering teachers and parents at these upper campuses, who are unlikely to be able to return to classrooms before February.

Parents say the limited reopening will make remote learning a disaster, with the health-mandated small, in-person class sizes resulting in extra-large virtual classes.

The school system, however, is struggling to line up enough staff for even a limited return to school buildings. The Washington Teachers’ Union says it is unsafe for its teachers to go back, and many are refusing to do so.

The union also wants widespread on-site coronavirus testing. It got some of what it asked when the city announced Thursday that it would provide on-campus rapid testing to any student or staff member who is symptomatic. D.C. Health Director LaQuandra S. Nesbitt said the District would have a “liberal” policy to determining who qualifies as symptomatic.

The city and the union continue to negotiate on an agreement that would guide school reopening. Chancellor Lewis D. Ferebee faced another setback this week after the city’s labor board ruled in favor of the teachers union, saying that the city has failed to collectively bargain with the union in reopening plans. City officials say they will abide by the panel’s rulings and are still assessing what the decision means for them.

“Our mission is to get young people back into our schools who need it and who choose to be there,” Ferebee said. “Each day we go by and we do not have that solution is a day that I worry about us not delivering on what needs to be done for our students and families.”

The chancellor said he is optimistic about reaching an agreement with the union and planned to continue negotiations Thursday afternoon. The big sticking points include masks and building inspections. Teachers want N95 masks for certain staff members. The chancellor has said those are hard to acquire and that he does not believe they are necessary.

The two parties have agreed that buildings will not be allowed to reopen unless they meet certain safety standards. But the union wants one of its representatives to sign off and verify that buildings have met these standards. The chancellor disagrees and, when asked Thursday, did not appear to budge on the issue. He said union representatives are not qualified to make these assessments and that only certified professionals should be allowed to do so.

An agreement with the union is critical to persuading enough teachers — about 700 would be needed to teach 7,000 children — to return to campuses next month.

Alecia Francis, a fourth-grade teacher at Ludlow-Taylor Elementary in Northeast Washington, said she is unsure who from her school is being called to teach in person, but said she lives with immunocompromised relatives and would not return if asked.

She said the city has not gathered teacher input and has not built trust for reopening plans. “I did not feel there was any transparency; I did not feel like I had any agency in this decision,” said Francis, who has taught at her school for 21 years.

“They have fumbled the plan. It has been a mess of rumors; every day, I have a friend who is texting and calling me and asking, ‘Did you hear?’ I don’t even know what’s going on,” Francis added.

Parents said they fear there are few winners in the mayor’s plan. Ferebee said virtual learning classes are expected to grow as the school system pulls teachers from their virtual classrooms to teach in-person classes of about 10 children. Students will also be assigned new teachers if they continue learning virtually and their teacher is pulled to teach an in-person class.

This issue is particularly acute in overcrowded elementary schools, which are most prevalent in Ward 3, the wealthiest part of the city. Ferebee said classrooms are capped at 40 students.

Andy Beck said his second-grader at Eaton Elementary in Northwest Washington just became comfortable with raising her hand in a virtual classroom. He worries what will happen if her class grows or she changes teachers just as she grows more at ease with remote learning.

“It’s reckless to disrupt the education of the vast majority  of students for a small number of students doing in-person learning,” Beck said. “It’s irresponsible, it’s destructive, and it’s disruptive.” 

An initial version of this story said D.C. Public Schools saw a decline of 22 percentage points in the number of kindergartners meeting literacy goals at the start of the school year compared to a year ago, and a nine percentage-point drop in students through second grade who are meeting these targets. The mayor’s office and school system later revised the figures to say there has been a decline of 11 percentage points in the number of kindergartners through second graders meeting literacy goals.